After prossessing Dracula's Heart, you can go to a new mansion with the Ferryman's help.
Go to Aljiba Woods
From the mansion entrance, go to the left to reach the area under Yuba Lake, then go up the stairs and jump up the platforms to leave the area. Go to the left, and carefully walk onto the moving platforms, then jump off on the other side. Keep going to the left until you are back in the area below the forest. Go up the long set of stairs.
Get Laurels and Garlic
If you don't have any Laurels, you should go to the right from here to reach Aljiba. You can buy Laurels. You will need at least one. Then go to the left to return to the Aljiba Woods.
Get the Chain Whip
Go to the left until you are in Dabi's Path (the cave with the eyeballs). Go to the left to reach the left half of Dabi's Path, and take the stairs down to the lower level, then go to the left to reach the town of Veros. If you haven't bought the Chain Whip, you should strongly consider buying it here in Veros for 150 hearts. You can also heal up here if you need to.
Go to the Ferryman
Now go to the left until you have reached the town of Jova, where you started the game. Heal up in the church in the upper part of town if necessary, equip Dracula's Rib, then use the left-hand exit of Jova. You will be in Belasco Marsh. Some Lizardmen will come toward you, spitting fireballs. Equipping Dracula's Rib will shield you from these. Go to the left, but be careful of the Wolf that leaps off of the platform toward you. Go left to the next platform, where another Wolf will rush toward you. Go to the left from there and you will find yourself at a poison swamp. Use a Laurel to walk through the swamp without getting hurt. You will also be immune to the monsters' attacks while the Laurel is in effect. Go to the left again to leave the marsh.
You will arrive at the Dead River. Go to the left, and walk onto the Ferryman's ferry. Equip Dracula's Heart, then talk to the Ferryman. If you equipped Dracula's Heart, he will say "let me show you the way", and the ferry will start moving. The Fishmen that jump out of the water can't hurt you, even if they jump right in front of you, so just ignore them.
When the ferry reaches the other side, jump off, because the Ferryman immediately goes the other way. Go to the left and you will be in front of Brahm's Mansion.
Get the Diamond
You can get a weapon before going to Brahm's Mansion. Go to the left from Brahm's Mansion and you will find some platforms floating over the water. Carefully make your way across. For most of the platforms, you should wait until the platform is almost at the top before you jump to the next one, because you jump farther when you jump from a platform that is moving upward. HOWEVER! When you get to the platforms that are closer together than the others, you should jump when the platform is almost at the bottom. This will ensure that you make a short jump, instead of jumping too far and going past the next platform.
When you reach the other side, go to the left to reach the Jam Wasteland. Kill the Mummy and go to the left, then kill the floating Phantoms that come toward you. Then equip Dracula's Rib and jump up to where there is a Venus Fly Trap. It will spit a fireball, but your shield will deflect it. Kill the Venus Fly Trap, then kill the Medusas that float toward you. Go to the left and you will find a Gypsy. Talk to him and he will give you a Diamond. This is a weapon that you can throw. It will bounce off any walls it hits, hurting any enemies that it hits along the way, making it most effective when used indoors.
Go to Brahm's Mansion
Go to the right from this dead end. Jump over the water platforms like before, then go to the right to reach Brahm's Mansion.